Gilead appears to be meeting or even exceeding Street expectations for the launch of its new hepatitis C pill Sovaldi.

Total prescriptions (TRx) for Sovaldi rose almost 70% to 1,764 for the week ended Jan. 10, according to IMS Health. Previous weeks included the holidays, so too much can be made about the week-over-week growth. Still, the Solvadi scripts to date are impressive and point to early, strong demand for the new Hep C pill.

ISI Group analyst Mark Schoenebaum is tracking the Sovaldi launch closely for his investor clients. Over the weekend, he sent out the following observations.

1. The total TRx for Sovaldi over the first five weeks of its launch (despite two major holidays) is >3x the TRx for Incivek over the first five weeks of its launch.

2. If TRx were to only remain flat through year end and we assume 20% discounting on price and a similar capture rate to Incivek for sales from IMS TRx, we estimate that FY 2014 sales could be ~$2.4 Bn. (The current sell side estimate for FY'14 Sovaldi sales is ~$2.5 Bn although my buy side surveys of US Sovaldi sales have suggested YOUR estimates have been higher, ~$3 Bn)

Schoenebaum gave me permission to share this chart his team created, which shows graphically how the Gilead Sovaldi commercial launch compares to Vertex Pharma's (VRTX) launch of Incivek.

Sovaldi is the blue line; Incivek in red.

Gilead shares closed Friday at $78.40 and are up 1.4% to $79.50 in pre-market trading Tuesday.

Adam Feuerstein writes regularly for TheStreet. In keeping with company editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback; click here to send him an email.